malavazos



Nov. 5, 1957 A. J. MALAVAZOS KEYBOARD 3 Sheets-Sfieet 1 Filed July 20.1954 FIE 1- Nov. 5, 1957 J. MALAVAZQS KEYBOARD 3 Sheets-Sheet 2 m MIH.mlu

Filed July 20, 1954 Nov. 5, 1957 A. J. MALAVAZOS KEYBOARD Filed July 20,1954 3 She ets-Sheet 3 :E'IIE- 5 IE'IE- 4 2,812,233 Patented Nov. 5,1957 Phi KEYBOARD Arthur J. Malavazos, Oakland, Calif., assignor toFriden Calculating Machine Co., Inc., a corporation of Catt forniaApplication July 20, 1954, Serial No. 444,477 12 Claims. (Cl. 235-145)This invention relates to calculating machine keyboards and moreparticularly to full keyboards of the character used in portablecalculating machines such as those manufactured by the FridenCalculating Machine Company of San Leandro, California.

It is among the objects of the invention to provide an improvedcalculating machine keyboard which has a much lighter and more uniformkey action than corresponding keyboards currently in use; which hasmeans accurately guiding the keys in their value selecting movementsand, at the same time, permits a loose fit between the key stems and thekey carrying frame so that the frame and key stems do not have to bemanufactured with the high degree of accuracy presently required; whichutilizes flat key stems so arranged that the operating pressures arebetween the fiat sides of the key stems and the keyboard frame therebyreducing wear of the stems and frame to an entirely negligible amount;which provides means for locking and releasing the key rows individuallyby operation of the corresponding keys, and control means for lockingand releasing the entire keyboard; and which provides a constructionthat is simple and economical to manufacture and assemble and easy toservice when necessary.

Other objects and advantages will become apparent from a considerationof the following description and the appended claims in conjunction withthe accompanying drawings wherein:

Fig. 1 is a fragmentary top plan view of a keyboard, illustrative of theinvention, parts being broken away and shown in cross-section to betterillustrate the construction thereof;

Fig. 2 is a longitudinal cross-sectional view on the line 2-2 of Fig. 1;

Fig. 3 is a fragmentary, transverse cross-sectional view on the line 3-3of Fig. 2; and

Fig. 4 is a fragmentary, transverse cross-sectional view on the line 44of Fig. 2.

With continued reference to the drawings, the numeral generallyindicates the keyboard frame, the numeral 11 generally indicates aplurality of digit keys mounted in the frame for manual operation, andthe numeral 12 generally indicates 0 keys disposed in a row across thefront portion of the keyboard frame.

The frame 10 comprises a flat upper plate 14 of rectangular shape havingkey stern receiving apertures 15 of elongated, rectangular shapeprovided therein and disposed in ordinally arranged rows extendinglongitudinally of the frame plate, the apertures being uniformly spacedalong the corresponding rows and having their major dimensions extendingalong the rows. The frame also comprises a flat, lower or bottom plate16 also of rectangular shape having at its front end an upwardly offsetflange portion 17 parallel to the front portion of the upper or topplate 14, said lower plate having elongated apertures 18 therein each inregistry with a corresponding aperture in the top plate 14. The plates14 and 16 are secured in spaced-apart and parallel relationship to eachother by a spacing plate 20 extending transversely of the frame betweenand perpendicular to the plates 14 and 16 near the front end of theframe and rigidly secured at its edges to the top and bottom frameplates and a similar spacing plate 21 extending transversely of theframe between the plates 14 and 16 near the rear end of the frame. Anadditional plate 22 is also disposed between the rear ends of the frameplates 14 and 16 to hold these plates in spaced-apart and parallelrelationship, the plates 20 and 22 having notches, as indicated at 23for the plate 20, extending downwardly from the upper edge thereof atlocations spaced apart therealong, and other spacing and fastening meansmay be used to further reinforce the connection between the plates 14and 16, if desired.

Each of the digit keys 11 comprises an elongated, flat stem 24 extendingthrough registering apertures 15 and 18 in the frame plates 14 and 16and having straight and substantially parallel edges and its majorcross-sectional dimension extending along the corresponding key row, ahead or block 25 secured on the upper end of the stem 24 in spacedrelationship to the upper surface of the top frame plate 14 and a pin 26projecting perpendicularly from the stem near the lower end thereof andbelow the bottom frame plate 16. A compression spring 28 surrounds eachkey stem 24 between the top plate 14 and the bottom end of thecorresponding key head 25 to raise the keys and, when a key is in raisedposition the pin 26 projecting perpendicularly from the lower endportion thereof bears against the under surface of the bottom frameplate 16 to limit upward movement of the key, the bottom surface of theplate 16 preferably being provided with strips of sound-deadening sheetmaterial which the pins engage so that the keys will not make a noise asthey are raised to their upper limiting position. At a location spacedbelow the corresponding head 25 each key is provided intermediate thewidth of one of the fiat sides thereof with a detent formation 30projecting from the fiat side of the key. These detent formations may beconveniently formed by pressing a portion of the key stem outwardly atone side of the key with a consequent depression of the material at theopposite side of the key stern and the formations all project from thesame sides of the key stems in each key row and preferably from the samesides of the stems in all of the rows. As is best shown in Fig. 3, eachdetent formation 30 has a flat top end 31 disposed in a planesubstantially perpendicular to the longitudinal center line of the keystem, a downwardly and inwardly inclined cam surface 32 at its lower endand a somewhat convex outer side having a bulge, as indicated at 33,immediately above the upper, outer end of the cam surface 32 on thelower end of the formation. Each key stem is also preferably providedwith an aperture 35 of rectangular shape extending upwardly from theupper end of the corresponding detent formation 30 medially of the widthof the key stem.

A plurality of bails 38 extend longitudinally of the keyboard frame 10between the frame plates 14 and 16 one along each row of key stems 24and at the sides of the stems of the corresponding row from which thedetent formations 30 project. Each of the bails 38 comprises a flatcross-member 40 of substantially rectangu lar shape, rounded legs 41 and42 projecting perpendicularly from the member 40 one at each endthereof, an extension 43 of the member 40 extending rearwardly beyondthe bail leg 42, and a flange 44 projecting perpendicularly toward thekey stems of the corresponding key row .from the edge of the member 40remote from the edge of this member nearest the legs 41 and 42 and lowerframe plate 16. Pivot pins 46 and 47 project outwardly from the legs 41and 42, respectively, coaxially of each other and through apertures inthe front and rear frame spacing plates 20 and 21 near the bottom frameplate 16, and the flange 44 is disposed near the under surface of thetop frame plate 14 in position to engage over the upper ends of the keystem detent formations 30 when the keys are depressed. Arms 48 and 49project perpendicularly from the outer edge of each bail flange 44 in adirection away from the corresponding cross-member 40 of the bail andeach arm 48 and 49 is provided at its outer end with anupwardlyextending lug formation, as indicated at Siland 51, extendingthrough corresponding apertures 52 in thetop plate 14, the arms 48 beingdisposed near the forward ends and the arms 49 near the rearward ends ofthe corresponding bails. Additional arms 36 project perpendicularly, onefrom each bail flange between the corresponding .arms 48 and 49 andsprings 37 are connected one between each arm 36, at the outer endthereof, and the frame plate 16 and resiliently rock the correspondinghails in adirection to bring the outer edges of .the bail flanges intoposition to engage the detent formations 30 on the key stems of anydepressed digit keys.

Each of the keys 12 has a flat stem 54 slidably mounted in registeringapertures in the upper and lower frame plates 14 and 16 and each ofthese stems carries on its upper end a key head 55 having a recess inits forward side so that the 0 keys can be manually raisedabove theirnormal position or manually depressed. A compression spring 56 surroundseach 0 key stem 54 between the top plate 14 and the bottom end of thekey hand 55 .to resiliently urge the 0 keys upwardly to their normalraised position.

Each bail is rocked to release any depressed digit key in thecorresponding key row when the 0 key at the endof the same row ismanually depressed. In order to accomplish this action the front leg 41of each bail 40 is provided with a straight cam edge 58, inclinedupwardly and toward the upper edge of the bail strip, and each "0 keystem has a rearwardly projecting extension or arm 59 which engages thecam edge 58 on the adjacent leg of the corresponding bail and rocks thebail in a direction to move the bail flange 48 away from the key stemswhen the 0 key is depressed.

A plurality of bellcrank levers 60 are disposed between the frame plates14 and 16 each adjacent the side of a corresponding "0 key stem and eachbellcrank lever is pivotallymounted at its angle on the associated 0 keystem 54 by aheaded pin 61 extending perpendicularly from the "0 key stemand through the corresponding bellcrank lever. Each 'bellcrank leverbears at its upper end against the underside o'fthe top frame plate 14just forwardly of the associated 0 key stem and bears at its rearwardedge below the pivot pin 61 against the front end of the pivot pin 46ofthe correspondinglatch bail 40. With this arrangement, whenever a 0 keyis raised above its normal up position, the associated bellcrank lever60 is rocked about its pivot pin 61 and bears against the bail pivot pin46 with which it is engaged to force the corresponding bail rea1wardly.Each of the apertures 52 in the top frame plate 14 has a rearwardportion substantiallynequal to the width of the corresponding lugformation 50 and a forward portion wider than the rearward portion byranamount sufiicient to permit rocking movement of the corresponding bailfor latching and unlatching the detent formations on the correspondingdigit keys, the wider portion of reach aperture .52 being joined to thenarrower portion thereof by an inclined carnshoulder 62. When a bail 'isforced .rearwardly the lugs 50 and 51 thereon are forced into the narrowrearward .por tions of the corresponding apertures '52 and the -bail isthereby locked against rocking movement inposition'to latch down anydepressed digit key and lock against depression any raised key in thecorresponding "row 'of keys. The depressed key in any row can thus belocked in latched-down position by merely raising above its normal up orraised position, the 0 key at the front end of the same row of keys.

A tension spring 64 connected between each bellcrank 60 immediatelyabove the corresponding pivot pin 61 and the spacer plate 20 resilientlyurges each bellcrank lever to rock in a direction to release theassociated bail for forward movement when the "0 key is returned to itsnormal position.

When a depressed 0 key is released, rocking movement of the associatedbellcrank lever 60 by spring 64 is terminated by engagement of the frontedge of the bellcrank lever with a stop pin 63 carried by the key stem54 below the pivot pin 61.

A flat spring 65 is secured between the rear spacer plate 22 and anupwardly directed flange 66 extending across the rearward end of thebottom frame plate 16 and this spring is provided with a plurality ofspring fingers 67 each of which bears against the rearward end of therearward extension 43 of a corresponding bail 40 and resiliently urgesthe bail in a forward direction, any bail that has been locked byraising of the corresponding 0 key being moved forwardly to its releasedposition upon return of the 0 key to normal position.

Suitable means are also provided for simultaneously locking all of thelatch-down bails in key-latching position and this means, asillustrated, comprises a bail, generally indicated at 68, having acrossbar .69 extending through registering apertures 70 in thelatch-down bails 40 and connected by legs, as indicated at 71, extendingone from each end of .the crossbar .69, to a rock shaft 72 which extendstransversely of the keyboard between the lower edges of the latch-downbails 40 and the bottom frame plate 16 of the keyboard frame. Theapertures 70 are elongated longitudinally of the latch-down bails 40 andthe bail crossbar 69 is normally'at the rear ends of these apertures sothat the bails 40 can be individually moved rearwardly by raising of thecorresponding 0 keys 12, as explained above, and will be collectivelymoved rearwardly when the bail 68 isrocked in a rearward direction or ina clockwise direction, as viewed in Pig. 2. When the bail 68 is releasedthe spring fingers 67 will return all of the latch-down bails40forwardly from their locked position.

Suitable means are also provided for simultaneously moving all of thelatch-down bails 40 away from their key-latching position to release allof the depressed keys of the keyboard when it is desired to completelyclear the keyboard and this means comprises a flat bar 74 extendingthrough registering aperture 75 of substantially square shape in thelatch-down bails .0 near the front ends of these bails. The bar 74 isprovided at locations spaced apart along its upper edge with upwardlyprojecting abutment formations 76 each .of which engages the portion ofthe associated latch-down bail 40 between the upper edge of thecorresponding aperture 75 and the bail flange 44 so that, when the bar'74 is moved to the right, as viewed in Fig. '3, all of thelatch-down'bails '40 will be rocked to release any keys held inlatched-down position by the bails. Both manually operated and machineoperated mechanisms may be provided to move the bar '74 so that the keyscan be released at the will of the operator and will be automaticallyreleased at the termination of a calculating operation of the associatedcalculating machine.

A pair of selection bars, as indicated at 77 and 78, are disposed insubstantially vertical position below each row of digit keys '11 andeach of these selection bars is provided in its upper edge with camnotches, as indicated at '80 for the 'bar '77 and 81 for the bar 78,whichare engaged by the pins 26 of the corresponding digit keys todifferentially shift the bars 77 and'78 forwardly to-condition theactuating 'rnec'hanism of the calculating chine to enter selected"values 'in'the'machine register, in

a manner well known to the art. The bar 77 is supported near its frontand rear ends for longitudinal movement on upwardly extending pivotedlinks 82 and 83 and the bar 78 is similarly supported on upstandingpivoted links 84 and 85. The bar 77 is disposed at the left-hand side ofthe bottom ends of the corresponding row of key stems 24 and is actuatedby the keys numbered from 1 to 5 of the corresponding key row, the pins26 carried by these key stems extending to the left from the lower endportions of the associated key stems, and the bar 78 is positioned atthe right-hand side of the same row of key stems and is actuated by the6 to 9 keys, inclusive, of the corresponding key row, the pins 26carried by these keys projecting to the right from the lower endportions of the corresponding key stems.

- A guide plate 86 is disposed at one side of each pair of selectionbars 77 and 78 and each such guide plate is of elongated, rectangularshape and is rigidly supported at its front and rear ends by a fronttransverse frame member 87 and a rear transverse frame member 88, thesetransverse frame members constituting a portion of the machine frame andextending transversely of the machine in parallel and spaced-apartrelationship to each other below the keyboard of the machine.

Each guide plate 86 is provided with a substantially straight upper edgepositioned immediately below the bottom surface of the lower frame plate16 of the keyboard and is also provided with notches 90 of rectangularshape extending downwardly from the top edge thereof at locations spacedapart along the guide bar to respectively receive the pins 26 projectingfrom the lower end portions of the key stems of the adjacent rows ofkeys. Each notch 90 has a length transversely of the corresponding guideplate sufiicient to permit free up-and-down movement of thecorresponding digit keys as these keys are manually depressed andreleased and has a Width substantially equal to the diameter of the pins26, the guide notches providing just sufficient clearance for freemovement of the pins therethrough. At its upper end each notch is flaredoutwardly, as indicated at 91, to guide the corresponding pins into theupper ends of the notches when the keyboard is being assembled with themachine, the pins being rigidly held to straight line movements afterthey have entered the notches and the guide plates being effective totake up the reaction between the pins and the corresponding selectionbars 77 and 78 as downward movements of the pins moves the selectionbars forwardly against the spring resistance.

With this arrangement, it is not necessary to maintain any close fit ortolerance between the side edges of the key stems and the apertures inthe plates 14 and 16 through which the key stems extend and there is nowear between the edges of the key stems and the ends of the key stemreceiving notches since no pressure is applied between these surfaces.Also, with the rockable latchdown bails 40, it is not necessary tomaintain a close fit between the sides of the key stems and the sides ofthe key stem receiving apertures in the keyboard frame plates and noappreciable wear occurs between the sides of the key stems and thelongitudinal edges of the frame plate apertures since the areas involvedare relatively large and there is no definite pressure which would tendto cause wear. There is also no appreciable wear between the pins 26 andthe sides of the notches 90 in the guide plates 86 since the pins are ofsmooth, cylindrical shape and are hardened and the sides of the notches90 may be made entirely smooth and the guide plates may also be hardenedto minimize wear. If, after a long period of service, sufficient wearshould occur in the notches 90 to affect the operation of the keys, itwould be a simple matter to replace the guide bars 86, retaining thesame keyboard in the machine.

. By the use of the rockable latch-down bails 40 and the laterallyprojecting latch detents on the key stems the action of the keys is madeuniform and extremely light,

wear between the key stems and the keyboard frame is substantiallyeliminated and accurate fitting of the key stems to the key stemreceiving apertures in the keyboard frame is rendered unnecessary. Byproviding for longitudinal shifting movement of the bails the depressedkey in any row can be locked in latched-down position by raising thecorresponding 0 key and all of the depressed keys of the keyboard can belocked in latched-down position by rocking bail 68 in the properdirection. With the latch-down bails 40 unlocked, any depressed key isreto return to its upper position by depression of another key in thesame key row, all latch-down keys being manually releasable by partialdepression of other keys in the same key row, and all of the latch-downkeys of the keyboard can be simultaneously released by operation of therelease bar 74. By taking up the reaction between the selection bars andthe actuating pins of the keys by the guide plates 86, wear between thekey stems and the key stem supporting frame incident to the pressurenecessary to move the selection bars is also eliminated.

The invention may be embodied in other specific forms without departingfrom the spirit or essential characteristics thereof. The presentembodiment is, therefore, to be considered in all respects asillustrative and not restrictive, the scope of the invention beingindicated by the appended claims rather than by the foregoingdescription, and all changes which come within the meaning and range ofequivalency of the claims are, therefore, intended to be embracedtherein.

What is claimed is:

l. A calculating machine keyboard comprising a frame having spaced-apartupper and lower plates provided with key stem receiving apertures, digitkeys disposed in ordinally arranged rows extending longitudinally ofsaid frame and each comprising a flat stem extending slidably throughsaid frame plates with its major transverse dimension extending alongthe corresponding key row, a head on one end of said stem in spacedrelationship to the outer side of said upper plate, a key raisingcompression spring disposed between said upper plate and said key head,a pin projecting perpendicularly from the other end of said stem andmovable away from and toward the outer surface of said lower plate, anda detent formation projecting from one side of said stem between saidplates, bails extending longitudinally of said frame between said platesand one along each key row and each pivotally connected at its loweredge to said frame adjacent to said lower plateand having an offsetflange extending along its upper edge for movement toward and away fromthe key stems of the corresponding key row for engaging the stem detentformations of depressed keys of the corresponding key row, and springmeans connected between said frame and said bails resiliently urgingsaid bails in their detent engaging direction.

2. A calculating machine keyboard comprising a frame having spaced-apartupper and lower plates provided with key stem receiving apertures, flatkey stems slid-ably mounted in said plates for longitudinal movement anddisposed in ordinally arranged rows with the major transverse dimensionsof each stem extending along the corresponding row, each key sternhaving a detent formation projecting from one side thereof, bailsdisposed between said plates and extending one along each row of keysterns at the sides of said stems from which said detent formationsproject, each of said bails being ivoted to said frame adjacent saidlower plate and having a longitudinally extending flange engageable withthe detent formation on the stem of any depressed key in thecorresponding row to hold the key in latched-down position, and springmeans connected between each bail and the frame resiliently urging eachbail in its detent engaging direction.

3. A calculating machine keyboard comprising a frame, digit keysdisposed in ordinally arranged rows extending longitudinally of saidframe and each including a flat key stern extending through and slidablymounted for longitudinal movement in said frame with its majortransverse dimension extending along the corresponding row and providedwith a detent formation projecting from one side thereof within saidframe, bails extending longitudinally of said key rows within said frameand each pivotally connected to said frame for rocking movement into andout of engagement with the detent formations on the key stems of thecorresponding key row, .spring means connected between said bails andsaid frame resiliently urging said bails into engagement with the detentformations on the stems of any depressed keys in the corresponding rows,keys disposed one at one end of each ordinal row of digit keys and eachhaving a stem mounted for longitudinal movement in said frame, a camformation on the end of each bail adjacent the corresponding 0 key stem,and an extension on each 0 key stern engaging the cam formation on thecorresponding bail and effective to move the corresponding bail againstthe force of said spring means to release any latched-down digit key inthe corresponding key row when a 0 key is depressed.

4. A calculating machine keyboard comprising a frame includingspaced-apart and substantially parallel plates having key stem receivingapertures therein, digit keys disposed in ordinally arranged rows andeach having a fiat key stem extending slidably through said frame, eachkey stem having its major transverse dimension extending along thecorresponding row and having a latching detent projecting from one sidethereof, key-latching bails extending one along each row of key stemsbetween said plates and adapted to engage detent formations on key stemsin the corresponding rows to latch depressed keys in depressed position,spring means connected between said bails and said frame resilientlyurging said bails in their key-latching direction, one of said frameplates having apertures therein tapering in width from one end to theother and each of said bails having a lug formation received in acorresponding tapered aperture in said one frame plate and efiectivewhen at the narrow end of the corresponding aperture to hold theassociated bail in keylatching position and when at the wide end of thecorresponding aperture to free the associated bail for movement out ofkey-latching position, 0 keys disposed one at one end of each row ofdigit keys and each having a stem extending slidably through said frame,means acting between each 0 key stem and the corresponding bail to movethe bail to key releasing position when the 0 key is depressed, andmeans acting between each 0 key and the corresponding bail to move thebail longitudinally and bring the lug formation thereof into the narrowend of the corresponding lug receiving aperture in said one frame platewhen the 0 key is manually raised to thereby lock the associatedkey-latching bail in keylatching position.

5. A calculating machine keyboard comprising a frame includingspaced-apart and substantailly parallel plates having key stem receivingapertures therein, digit keys disposed in ordinally arranged rows andeach having a fiat key stem extending slidably through said frame, eachkey stem having its major transverse dimension extending along thecorresponding row and having a latching detent projecting from one sidethereof, key-latching bails extending one along each row of key stemsbetween said plates and adapted to engage detent formations on key stemsin the corresponding rows to latch depressed keys in depressed position,spring means connected between said balls and said frame resilientlyurging said bails in their key-latching direction, one of said frameplates having apertures therein tapering in width from one end to theother and each of said bails having at least one lug formation receivedin a corresponding tapered aperture in said one frame plateand-effective when at the narrow end of the co sp nd g aperture to lockthe associated bail in key-latching po ition and when at the wide end ofthe correspond ng aperture to free the associated bail for movement outof key latching position, 9 keys dis posed one at ne n of e h row 'ofdigit k ys and each having a st m ex n ing slida y hrough said frame.means acting between each 0 key stem and the com spending key-latching bil to move the bail to key re leasing position when'the 0 key isdepressed, means acting ween e ch 0 key and the correspondingkeylatehins bail to e the [bail lenaitndinallv and bring the lugformation er n into he narrow end of the cone-' sponding lug receivingaperture in said one frame plate,

when the 0 key is man ally raised, a rockable bail extending v rsely ofsaid frame and engaging said key:

latching bails to move all of said keyelatching bails longitudinally atthe same :time to bring the lug formations on said key-latching bailsinto'the narrow ends of the cor responding lug receiving apertures insaid one frame plate,

and spring means acting between said frame and said key-latching bailsresiliently urging said key-latching bails to move longitudinally in adirection to bring the lug formations thereon into the wider ends of thecorresponding lug receiving apertures in said one frame plate.

6. A calculating machine keyboard comprising a frame includingspaced-apart and substantially parallel plates having key sternreceiving apertures therein, digit keys disposed in :ordinally arrangedrows and each having a flat stem extending slidably through said frame,each key stern having its major transverse dimension extending along thecorresponding key row and having a latching detent projecting from oneside thereof, key-latching bails extending one along each row of keystems between said plates and adapted to engage detent formations on keystemsin thecorresp onding rows to latch depressed keys indepressedposit-ion, spring means connected between said bails and saidframe resiliently urging said bails'in their key-latching direction, oneof said frame plates having apertures therein tapering in width from oneend to the other and each of said bails having a lug formation receivedin a corresponding tapered aperture in said one frame plate andeffective when at the narrow end of the corresponding aperture to lockthe associated key-latching bail in key-latching position and when atthe Wide end of the corresponding aperture to free the associatedkeylatching bail for movement out of key-latching position, 0 keysdisposed one at one end of each row of digit keys and each having a stemextending slidably through said frame, means acting between each -O keystem and corresponding bail to move the bail to key-releasing positionwhen the .0 key is depressed, means acting between each 0 key and thecorresponding bail to move the bail longitudinally and bring the lugformation thereon into the narrow end of the corresponding lug receivingaperture in said one frame plate when the 0 key is manually raised, arockable 'bail extending transversely of said frame and engaging saidkey-latching bails to move all of sanl key-'latchingbails longitudinallyat the same time to bring theilug formations on said key-latching bailsinto the narrow ends of the corresponding lug receiving apertures insaid one frame plate, spring means acting between said frame and saidkeyt h bails resiliently urging said key-latching balls to movelongitudinally in a direction to bring the lug formations thereon intothe wider ends .of the corresponding lug receiving apertures said oneframe plate, and means effective to simultaneously move all of saidkey-latching bails to key releasing position comprising a longitudinallymovable bar extending transversely of said key-latching bails and havingdetents thereon individually engaging said key-latching stems extendingslidably through said frame and each stem having its major transversedimension extending along the corresponding key row and having a detentformation projecting from one side thereof, rockable bails extending onealong each key row and spring urged to engage the detent formations onthe stems of depressed keys to latch the depressed keys in depressedposition, means moving said bails against the force of said spring meansto release depressed keys of said keyboard, selection bar actuating pinsextending perpendicularly one from each key stem at one end of eachstem, and guide plates extending one along each key row adjacent saidframe and having guide notches therein individually receiving saidselecting bar actuating pins and holding said pins to straight linemovements against the reaction between said pins and the selecting barsWhen the corresponding keys are depressed and released.

8. In a calculating machine, a keyboard having a fiat frame, ordinallyarranged rows of digit keys having flat stems extending slidably throughsaid frame and each having its major transverse dimension extendingalong the corresponding key row and having a detent formation projectingfrom one side thereof, rockable bails extending one along each key rowand spring urged to engage the detent formations on the stems ofdepressed keys to latch the depressed keys in depressed position, meansmoving said bails against the force of said spring means to releasedepressed keys of said keyboard, selecting bar actuating pins extendingperpendicularly one from each key stem at one end of the key stem, andguide plates extending one along each key row adjacent said frame andhaving guide notches therein individually receiving said selecting baractuating pins and holding said pins to straight line movements againstthe reaction between said pins and the selecting bars when thecorresponding keys are depressed and released, said frame comprisingfiat plates secured in spaced-apart and parallel relationship to eachother and having apertures therein loosely receiving said key stems.

9. A calculating machine keyboard comprising a flat frame, ordinallyarranged rows of digit keys having flat stems extending slidably throughsaid frame and each having its major transverse dimension extendingalong the corresponding key row and having a latching detent formationprojecting from one side thereof, rockable keyurged to key-latchingposition, and manually operated means carried by said keyboard andeffective upon each row of digit keys individually to alternatively lockdepressed digit keys in depressed position or to free depressed digitkeys from said key-latching bails.

10. A calculating machine keyboard comprising a flat frame, ordinallyarranged rows of digit keys having flat stems extending slidably throughsaid frame and each having its major transverse dimension extendingalong the corresponding key row and having a latching detent formationprojecting from one side thereof, rockable keylatching bails extendingone along each key row and spring urged to key-latching position, andmeans engaging all of said key-latching bails and effective tosimultaneously lock all of said key-latching bails in key-latchingposition.

11. A calculating machine keyboard comprising a flat frame, ordinallyarranged rows of digit keys having flat stems extending slidably throughsaid frame and each having its major transverse dimension extendingalong the corresponding key row and having a latching detent for mationprojecting from one side thereof, rockable keylatching bails extendingone along each key row and spring urged to key-latching position, andmeans directly engaging all of said key-latching bails and effective tosimultaneously move all of said key-latching bails to key-releasingposition.

12. A calculating machine keyboard comprising a flat frame, ordinallyarranged rows of digit keys having flat stems extending slidably throughsaid frame and each having its major transverse dimension extendingalong the correspondingly key row and having a latching detent formationprojecting from one side thereof, rockable keylatching bails extendingone along each key row and spring urged to key-latching position, meansengaging all of said bails and effective to simultaneously lock all ofsaid keylatching bails in key-latching position, and means engaging allof said key-latching bails and elfective to simultaneously move all ofsaid key-latching bails to keyreleasing position.

latching bails extending one along each key row and spring Britton Mar.11, 1930 Hilder Apr. 25, 1933

